544 research outputs found

    Safety ranking definition for infrastructures with high PTW flow

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    Powered two-wheelers (PTWs) provide a suitable mode for a large portion of population in many cities due to rider's personal convenience and the vehicle supposed easiness of manoeuvring. At the same time PTWs present serious safety issues compared to other motorized vehicles. This paper reports the main outcome of study carried out in Rome, where this mode is very popular and assesses the economic efforts to make infrastructure safer for PTWs. The methodology, extensively described in the paper, includes three steps: the accident analysis, the development of economic indicators of accidents costs, the maintenance priority. In the first step the location of the PTWs local accidents are identified, then the accidents are analyzed by means of the suitable indicators and, among these the safety potential (SAPO). Lastly, according to the results of the analyzed indicators the need of infrastructure maintenance will be defined. Usually SAPO is applied to rural areas, but here it has been adapted to describe the phenomena of the urban area in hand. As a result, the estimation of the saving potential to improve the infrastructure safety levels, thus reducing the amount of accidents, is presented, along with recommendations on how to upscale the SAPO at city level

    Headway in large-eddy-simulation within the SPH models

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    In the present paper we show some preliminary resuslts of a novel LES-SPH scheme that extends andgeneralizes the approach described in [2]. Differently from that work, the proposed scheme is based on the definition of a Quasi-Langragian Large-Eddy-Simulation model where a small velocity deviation is added to the actual fluid velocity. When the LES equations are rearranged in the SPH framework, the velocity deviation is modelled through the Particle Shifting Technique (PST), similary to the δplus-SPH scheme derived in [3]. The use of the PST allows for regular particle distributions, reducing the numerical errors in the evaluation of the spatial differential operators. As a preliminary study of the proposed model, we consider the evolution of freely decaying turbulence in 2D. In a particular we show that the present scheme predicts the correct tendencies for the direct and inverse energy cascades

    Materials study to implement a 3D printer system to repair road pavement potholes

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    InfraRob is a research project funded by the European Commission's research programme Horizon 2020 that aims to maintain integrity, performance, and safety of the road infrastructure through autonomous robotized solutions and modularization. A specific task of the project is focused on the development of a system 3D printer able to extrude a specific mixture for filling in small cracks and potholes, to be integrated with an existing small autonomous carrier. The first step of the research deals with the definition of the optimal parameters of the system 3D printer/mixture, by studying in parallel the material design and the printer design. This paper presents the study performed on a mixture chosen among those commonly used for road potholes repair. The mixture is studied to achieve and balance the different conflicting performances: consistence, flowability homogeneity, and internal structure. In addition to the basic components, the use of special additives has also been explored to improve the plasticity and adhesivity of the mixture. The first phase of tests is conducted to define the main printing controls: i) Extrudability control: materials for 3D printing need to have an acceptable degree of extrudability, which is related to the capacity of a material to pass continuously through the printing head; ii) Flowability control, to ensure the mixture can be easy-pumpable in the delivery system and easy-usable on the crack or the pothole to be filed-in; iii) Setting time control: printing material requires a certain setting time to maintain a consistent flow rate for good extrudability, thus appropriate additives are needed to control the setting time. The second phase includes in situ tests to verify the compaction of the mixture under the traffic loads. The paper presents the results of the lab and in situ tests, and the features of the chosen mix, suitable to be managed by the 3D printer

    Sentient Spaces: Intelligent Totem Use Case in the ECSEL FRACTAL Project

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    The objective of the FRACTAL project is to create a novel approach to reliable edge computing. The FRACTAL computing node will be the building block of scalable Internet of Things (from Low Computing to High Computing Edge Nodes). The node will also have the capability of learning how to improve its performance against the uncertainty of the environment. In such a context, this paper presents in detail one of the key use cases: an Internet-of-Things solution, represented by intelligent totems for advertisement and wayfinding services, within advanced ICT-based shopping malls conceived as a sentient space. The paper outlines the reference scenario and provides an overview of the architecture and the functionality of the demonstrator, as well as a roadmap for its development and evaluation

    Interpreting physical performance in professional soccer match-play: Should we be more pragmatic in our approach?

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    Academic and practitioner interest in the physical performance of male professional soccer players in the competition setting determined via time-motion analyses has grown substantially over the last four decades leading to a substantial body of published research and aiding development of a more systematic evidence-based framework for physical conditioning. Findings have forcibly shaped contemporary opinions in the sport with researchers and practitioners frequently emphasising the important role that physical performance plays in match outcomes. Time-motion analyses have also influenced practice as player conditioning programmes can be tailored according to the different physical demands identified across individual playing positions. Yet despite a more systematic approach to physical conditioning, data indicate that even at the very highest standards of competition, the contemporary player is still susceptible to transient and end-game fatigue. Over the course of this article, the author suggests that a more pragmatic approach to interpreting the current body of time-motion analysis data and its application in the practical setting is nevertheless required. Examples of this are addressed using findings in the literature to examine: a) the association between competitive physical performance and ‘success’ in professional soccer, b) current approaches to interpreting differences in time-motion analysis data across playing positions and, c) whether data can realistically be used to demonstrate the occurrence of fatigue in match-play. Gaps in the current literature and directions for future research are also identified

    Acromioclavicular joint reconstruction implants have differing ability to restore horizontal and vertical plane stability

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    Purpose Persistent acromioclavicular joint (ACJ) instability following high grade injuries causes significant symptoms. The importance of horizontal plane stability is increasingly recognised. There is little evidence of the ability of current implant methods to restore native ACJ stability in the vertical and horizontal planes. The purpose of this work was to measure the ability of three implant reconstructions to restore native ACJ stability. Methods Three groups of nine fresh-frozen shoulders each were mounted into a robotic testing system. The scapula was stationary and the robot displaced the clavicle to measure native anterior, posterior, superior and inferior (A, P, S, I) stability at 50 N force. The ACJ capsule, conoid and trapezoid ligaments were transected and the ACJ was reconstructed using one of three commercially available systems. Two systems (tape loop + screw and tape loop + button) wrapped a tape around the clavicle and coracoid, the third system (sutures + buttons) passed directly through tunnels in the clavicle and coracoid. The stabilities were remeasured. The data for A, P, S, I stability and ranges of A–P and S–I stability were analyzed by ANOVA and repeated-measures Student t tests with Bonferroni correction, to contrast each reconstruction stability versus the native ACJ data for that set of nine specimens, and examined contrasts among the reconstructions. Results All three reconstructions restored the range of A–P stability to that of the native ACJ. However, the coracoid loop devices shifted the clavicle anteriorly. For S–I stability, only the sutures + buttons reconstruction did not differ significantly from native ligament restraint. Conclusions Only the sutures + buttons reconstruction, that passed directly through tunnels in the clavicle and coracoid, restored all stability measures (A, P, S, I) to the native values, while the tape implants wrapped around the bones anteriorised the clavicle. These findings show differing abilities among reconstructions to restore native stability in horizontal and vertical planes. (300 words

    Proteomic profiling of retinoblastoma-derived exosomes reveals potential biomarkers of vitreous seeding

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    Retinoblastoma (RB) is the most common tumor of the eye in early childhood. Although recent advances in conservative treatment have greatly improved the visual outcome, local tumor control remains difficult in the presence of massive vitreous seeding. Traditional biopsy has long been considered unsafe in RB, due to the risk of extraocular spread. Thus, the identification of new biomarkers is crucial to design safer diagnostic and more effective therapeutic approaches. Exosomes, membrane-derived nanovesicles that are secreted abundantly by aggressive tumor cells and that can be isolated from several biological fluids, represent an interesting alternative for the detection of tumor-associated biomarkers. In this study, we defined the protein signature of exosomes released by RB tumors (RBT) and vitreous seeding (RBVS) primary cell lines by high resolution mass spectrometry. A total of 5666 proteins were identified. Among these, 5223 and 3637 were expressed in exosomes RBT and one RBVS group, respectively. Gene enrichment analysis of exclusively and differentially expressed proteins and network analysis identified in RBVS exosomes upregulated proteins specifically related to invasion and metastasis, such as proteins involved in extracellular matrix (ECM) remodeling and interaction, resistance to anoikis and the metabolism/catabolism of glucose and amino acids

    Functional conservation of the grapevine candidate gene INNER NO OUTER for ovule development and seed formation

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    Seedlessness represents a highly appreciated trait in table grapes. Based on an interesting case of seedless fruit production described in the crop species Annona squamosa, we focused on the Vitis vinifera INNER NO OUTER (INO) gene as a candidate. This gene encodes a transcription factor belonging to the YABBY family involved in the determination of abaxial identity in several organs. In Arabidopsis thaliana, this gene was shown to be essential for the formation and asymmetric growth of the ovule outer integument and its mutation leads to a phenotypic defect of ovules and failure in seed formation. In this study, we identified in silico the V. vinifera orthologue and investigated its phylogenetic relationship to INO genes from other species and its expression in different organs in seeded and seedless varieties. Applying cross-species complementation, we have tested its functionality in the Arabidopsis ino-1 mutant. We show that the V. vinifera INO successfully rescues the ovule outer integument growth and seeds set and also partially complements the outer integument asymmetric growth in the Arabidopsis mutant, differently from orthologues from other species. These data demonstrate that VviINO retains similar activity and protein targets in grapevine as in Arabidopsis. Potential implications for grapevine breeding are discussed
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